Indonesia has begun the first round of a nationwide campaign to vaccinate 24 million children against polio, which recently re-emerged in the country after a decade-long absence.

The Indonesian government says more than 750,000 health workers are at 245,000 immunization posts set up at health clinics, bus depots, railway stations and airports across the sprawling archipelago to give out the free vaccinations.

"Saya anak sehat" ["I am a healthy child"] sing children at a Jakarta immunization post after receiving the two drops of liquid that will protect them from the water-borne disease that often causes paralysis and can kill.

Doctor Ana Hasnani was on hand at the clinic and says she and her colleagues have spent days explaining to mothers in the neighborhood that the vaccine is safe. "I talked with not all, but some mothers, to explain to them," she said, "because they are afraid."

Indonesia has launched an unprecedented public information campaign to reassure parents about the vaccine.

Nearly a million children missed being vaccinated when high-risk areas were targeted in June, mostly because of unfounded rumors the vaccine had caused the death of three children.

The country's two largest Muslim organizations and local movie stars lent their support to the mass immunization program.

The U.N. Children's Fund national goodwill ambassador - movie star Ferry Salim - visited a number of immunization posts in Jakarta, thrilling children and their parents alike. "I am really sure that we can go through with this and Indonesia will be free of polio virus," said the movie star.

Indonesia had been free of polio since 1995, but in March a little boy was stricken with the disease. Since then, more than 225 children across the country have contracted the virus.

Indonesia is one of 16 countries re-infected with polio since 2003. In a major setback to the worldwide polio eradication initiative, Nigeria stopped immunization in 2003 because of false rumors the vaccine could result in HIV infection or sterilization, causing the virus to spread.

Claire Hajaj, a spokeswoman for the U.N. Children's Fund, says the success of Indonesia's mass vaccination is crucial to stopping the virus spreading across the region. "The first round today is critically, critically important not just for Indonesia, but for the entire region," she said. "This is an effort to stop polio virus here but also to stop it breaking out causing a regional infection."